Trucks are known which have a loading structure of variable configuration in accordance with the type of transportation to be effected and with the bulk of the material to be transported.
These trucks generally have one or more pairs of wheels the position of which is fixed relative to the main structure of the trucks. Parts of the frame can be variously oriented, joined together or telescopically retracted into the base frame to make it possible to achieve the various operative configurations of the truck.
Hand trucks in which some of the wheels are movable relative to the base frame structure by pivoting action have been proposed, see for example Australian patent specification No. 17001/76 and German Pat. No. 25 51 592.
The above trucks, although very practical in use, have the not negligible disadvantage of relatively high cost of manufacture and, therefore, relatively high selling prices, while in some cases there are also problems of weight and transportation.